| Range. | Strength of Wind. | ||
|---|---|---|---|
| Mild. Miles per hour, 10. | Fresh. Miles per hour, 20. | Strong. Miles per hour, 30. | |
| Deflection. | Deflection. | Deflection. | |
| 500 yards | 2 feet | 4 feet | 6 feet |
| 1,000 yards | 3 yards | 6 yards | 9 yards |
| 1,500 yards | 6 yards | 12 yards | 18 yards |
| 2,000 yards | 12 yards | 24 yards | 36 yards |
Note—Oblique Winds.—For oblique winds the approximate deflection at the above ranges may roughly be estimated as half that of a side wind of the same velocity and allowance in aiming-off may be made accordingly.
4. Exercises in Aiming-Off.—(i) Having memorized the approximate allowances for side and oblique winds of varying direction and velocity, as stated in para. 3, the recruit will next be taught to make allowance in aiming-off for wind at a full-length figure target on the range, according to the strength and direction of the wind which is actually blowing, or which may be supposed to be blowing, as given by the instructor. In carrying out these exercises the recruit should be taught to aim-off with reference to the breadth of a full-length figure target, which is rather less than 2 feet wide. Thus the amount of allowance will be measured as one breadth, two breadths, etc., to right or left.
5. Orders for Aiming-Off.—Finally, the recruit must be exercised in aiming-off at all ranges according to orders, the amount of allowance being given as so many times the breadth of the target indicated, or so many times the width of the intervals between targets consisting of close formations. The amount of allowance may also be indicated by the use of auxiliary aiming or description points (Sec. 45), as, for instance, a tree or bush, the lateral distance of which from the target equals approximately the required allowance. When none of these methods of indicating allowances are possible men must be taught to aim-off so many feet or yards to the right or left of the target, these measurements being taken as representing the lateral distance between the sight of the rifle and the target aimed at.
6. Method of Indicating Errors.—In aiming-off exercises it is necessary to employ a fatigue-man at the target to indicate the correct point of aim with a marking-disc after each aim taken by the recruit, which to commence with should be done with a rifle on an aiming-rest. He will carry out the duty according to previous instructions as to the correct point of aim for each exercise. The amount of allowance made by the recruit will be observed by the instructor with an aim-corrector, unless an aiming-rest is used. The recruit will be made to note his errors, which will be criticized by the instructor.
7. Instruction on Miniature Ranges.—Instruction in aiming-off can be carried out on miniature ranges, as described in Chapter X (see Practice No. 2, p. 227).
Section 21.—Aiming Up and Down.
1. When to Aim Up and Down.—The rifle will be aimed up or down to increase or reduce elevation at all ranges when there is no time to alter sights, as, for example, in firing at targets in movement, in repulsing a charge at close range, in case of surprise, when very slight alterations of elevation are seen to be necessary, as the result of observation of fire, and to avoid frequent small changes of sighting which lead to loss of fire effect. Correction of sighting in individual firing at close range is seldom possible in war. Therefore aiming up and down is the normal means of altering elevation in firing at targets within close range.
2. Rules for Aiming Up and Down.—There is no fixed rule for aiming up and down. As a general rule aim should be directed at a point not more than 3 feet above or below the six o’clock line, according to the position of the target beyond or short of the zone for which the sights are set. The degree of allowance in aiming up and down will depend on the rate and direction of movement and the range of the target, and will be a matter for individual judgment. If the difference between the range and the sighting exceeds 200 yards it will be best to alter the sighting.
3. Exercises in Aiming Up and Down.—To practise aiming up and down, under conditions approximating to those of service, the sights should first be fixed for a given range, and then fatigue-men or standing-figure disappearing targets disposed at various ranges should be alternately brought into view for short periods of time, representing troops in movement. Men should be told whether targets represent retreating or advancing troops, and aim up or down accordingly. Aim maybe criticized by using aiming-rests or aim-correctors.